To understand what a good logo is, we must first consider its purpose.

A logo is essentially a packaging tool.
Companies need a way to differentiate their products and services from those of their competitors, and they achieve this through unique stylization of the packaging, advertising and messaging they offer.
If logos and brands didn’t exist, there’d be no easy way to tell who we were buying from.
We’d have to read every label and every product description.
Products and services would then be reduced to their pure utility, and we’d only be able to determine a thing’s value on the basis of its actual function.
Imagine if every product, every restaurant and every company had exactly the same label, in the same type and with the same colors.
Wouldn’t that be a more boring world to live in?
So novelty is extremely important in the world of business, culture and branding.
Quite simply, a logo is the unique form that communicates the ownership of a particular good or service.

A good logo is distinctive, appropriate, practical, graphic and simple in form, and conveys the message intended by its owner.
A concept or meaning usually lies behind an effective logo, and it communicates the desired message.
A logo should be able to be printed in any size and, in most cases, be effective without color.
A good logo essentially boils down to two things: a good concept and good execution.

When creating a logo, follow the typical process followed by professional logo designers to ensure that the final design meets requirements.
The first step is to produce a design brief, then research the project area and successful logos , and finally make a sketch, until you arrive at a satisfactory result.

A good logo conveys the right message.

The following five principles should be followed to ensure that the creation meets all these criteria:

Simple: Simplicity makes a logo easily recognizable, versatile and memorable.
Good logos present something unexpected or unique, without being overdone.

Memorable: This principle of simplicity is closely followed by that of memorability.
An effective logo must be memorable, and this can be achieved by keeping it simple, yet appropriate.

Timeless: An effective logo must be timeless.
Will the logo stand the test of time?
Will it still be effective in 10, 20 or 50 years?

Versatile: An effective logo works on a wide variety of media and applications.
That’s why logos should be designed in vector format, to fit any size.

Appropriate: The way you “position” the logo should be appropriate for the audience it’s intended for.
For example, a childlike font and color palette might be appropriate for a children’s toy store logo, but not so much for a law firm.